US7547336B2 - Vacuum cleaner with multiple cyclonic dirt separators and bottom discharge dirt cup - Google Patents

Abstract

A vacuum cleaner comprises a cyclonic separator having a first cyclone and a plurality of downstream secondary cyclones. The first cyclone comprises a side wall defining a first cyclonic chamber, and the secondary cyclones each comprise a side wall defining a second cyclonic chamber. A dirt cup assembly is mounted below the cyclonic separator to collect contaminants separated in the first and second cyclonic chambers. The secondary cyclones can be arranged around the first cyclone side wall and form a gap between adjacent secondary cyclones so that the first cyclone side wall is exposed at the gap. A working air conduit can extend through the first cyclone and the dirt cup assembly to couple the secondary cyclones to a suction source located below the dirt cup assembly. Furthermore, the secondary cyclones can have a vortex stabilizer.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. patent application Ser. No. 60/593,125, filed Dec. 13, 2004, which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a vacuum cleaner with a cyclonic dirt separator having a first cyclone and a plurality of downstream secondary cyclones. In one of its aspects, the invention relates to a cyclonic dirt separator with secondary cyclones arranged around the first cyclone to provide an unobstructed view of at least a portion of the first cyclone. In another of its aspects, the invention relates to a cyclonic dirt separator with a dirt cup assembly mounted below the cyclones and a working air conduit that extends through the first cyclone and the dirt cup assembly. In another of its aspects, the invention relates to a cyclonic dirt separator with secondary cyclones having a vortex stabilizer.

2. Description of the Related Art

Cyclone separators are well-known. Some follow the textbook examples using frustoconical shape separators, and others use high-speed rotational motion of the air/dirt to separate the dirt by centrifugal force. Typically, working air enters and exits at an upper portion of the cyclone separator, and the bottom portion of the cyclone separator is used to collect debris. Furthermore, in an effort to efficiently distribute weight of and upright vacuum cleaner, the suction source that creates the working air flow is typically placed at the bottom of a handle assembly and below the cyclone separator. This arrangement, therefore, requires an exhaust air path from an upper portion of the cyclone assembly and down the handle to the suction source. This airpath can be tortuous and formed by multiple parts that can allow for air leaks, which negatively impact airflow and, necessarily, cleaning performance.

U.S. Pat. No. 6,238,451 to Conrad discloses a cyclonic separator in a vacuum cleaner comprising a single first stage cyclone and a plurality of vertically aligned secondary downstream cyclones arranged in parallel relative to one another. The secondary cyclones are located within the same perimeter of and directly above the upstream cyclone. This arrangement of cyclones necessarily creates a tall unit because the downstream cyclones are located above the upstream cyclone.

U.S. Pat. No. 6,607,572 to Dyson discloses a cyclonic separating apparatus with upstream and downstream cyclonic units, wherein the downstream units comprise a plurality of downstream cyclones located above the upstream cyclone and inverted relative to the upstream cyclone.

U.S. Pat. No. 6,070,291 to Bair et al. and its progeny shortens the air path from the cyclone exhaust to the motor inlet. These patents disclose a pleated cylindrical filter in a cyclonic chamber whereby the working air is drawn through the cylindrical filter, through the bottom of the cyclonic chamber, through another filter, and directly into the suction source inlet. The suction source is in a vertical position below the cyclonic chamber. The vertical orientation of the suction source is undesirable due to the amount of space needed at the bottom of the handle to accommodate the suction source in this position. Additionally, the motor shaft of the vertically oriented suction source cannot be utilized to power a horizontal axis agitator.

U.S. Pat. No. 6,341,404 to Salo et al. discloses a bottom discharge cyclone chamber with the suction source mounted horizontally below the cyclone chamber. However, motor exhaust air is redirected back up into an annular exhaust plenum located below the cyclone chamber, and the motor exhaust exits from the exhaust plenum in a radial fashion. This exhaust path includes a number of turns, which tend to create backpressure and, therefore, reduce efficiency.

U.S. Pat. No. 6,129,775 to Conrad discloses a cyclone separator with a number of different forms of flow inhibitors, such as a terminal insert, to interfere with airflow within the cyclone separator. As shown inFIG. 14(d), the terminal insert can comprise a plurality of longitudinally extending members, such as rods, which extend upwardly into the cyclone separator cavity from the bottom surface of the cyclone separator. The rods are said to interact with circulating fluid to disrupt its rotational motion. The rods can be positioned symmetrically or non-symmetrically around longitudinal axis of the separator. The rods can be a variety of shapes such as, in transverse section, squares, ellipses or other closed convex or abode shapes. Further, the transverse section of rods can vary longitudinally.

U.S. Patent Application Publication No. 2005/00500678 to Oh et al. and its progeny disclose a cyclone dust separating apparatus comprising a primary cyclone and a plurality of downstream secondary cyclones arranged around the primary cyclone. As a result of this configuration, the secondary cyclones obstruct the view of the primary cyclone, and the user cannot visually observe the operation of the primary cyclone. Additionally, the working air exiting the secondary cyclones exits the cyclone dust separating apparatus through an upper opening.

SUMMARY OF THE INVENTION

According to the invention, a vacuum cleaner comprises a cyclonic separator that includes a first cyclone having a side wall defining a first cyclonic chamber for separating contaminants from an air stream as the air stream travels about the first cyclonic chamber from an air inlet to an air outlet, and a plurality of secondary cyclones downstream from the first cyclone and arranged around the side wall of the first cyclone, each of the secondary cyclones having a side wall defining a second cyclonic chamber for further separating contaminants from the air stream as the air stream travels about the second cyclonic chamber from an air inlet to an air outlet thereof. The vacuum cleaner further includes a nozzle housing including a suction opening fluidly coupled with the air inlet of the first cyclonic chamber and a suction source coupled to the suction opening and to the first and second cyclonic chambers and adapted to establish and maintain the air stream from the suction opening, through the first cyclonic airflow chamber, and through the second cyclonic airflow chambers.

According to one embodiment of the invention, the secondary cyclones form at least one gap between adjacent secondary cyclones, and the first cyclone side wall is exposed to the outside of the cyclonic separator at the at least one gap.

Advantageously, the first cyclone side wall is preferably formed of a translucent material at least at the at least one gap to provide an unobstructed view of the first cyclonic airflow chamber through the first cyclone side wall and through the at least one gap in the secondary cyclones.

The vacuum cleaner typically further comprises an upright housing with an opening that receives the cyclonic separator, and the at least one gap is formed at a front portion of the cyclonic separator for an unobstructed view of the first cyclone side wall when the cyclonic separator is mounted to the upright housing.

In a preferred embodiment, the air inlet to the first cyclone is positioned in the side wall of the first cyclone and distal from the at least one gap. In another preferred embodiment, the secondary cyclones form two gaps, and the air inlet to the first cyclone is positioned in one of the two gaps. Preferably, the two gaps are formed at opposite sides of first cyclone side wall.

According to another embodiment of the invention, a vacuum cleaner further includes a dirt cup assembly mounted beneath the cyclonic dirt separator to collect the contaminants separated by the first cyclonic chamber and the second cyclonic chambers; and a working air conduit extending through the first cyclone and the dirt cup assembly and fluidly coupling the air outlets of the second cyclonic chambers to an inlet of the suction source.

In a preferred embodiment of the invention, the secondary cyclones are arranged in groups. In an exemplary embodiment of the invention, one of the groups of secondary cyclones comprises four of the secondary cyclones, and another of the groups comprises five of the secondary cyclones. Further, each of the groups of secondary cyclones is enclosed by a side wall spaced from the first cyclone side wall. Preferably, the enclosing side wall of the groups of secondary cyclones is translucent.

Typically, the secondary cyclones are arranged in parallel. Preferably, the secondary cyclones have a generally vertical central longitudinal axis parallel to a central longitudinal axis of the first cyclone. Further, the secondary cyclones are frustoconical, and the first cyclone is cylindrical.

In a preferred embodiment of the invention, the dirt cup assembly comprises a first collecting region for collecting the contaminants separated in the first cyclonic chamber and a second collecting region for collecting the contaminants separated in the second cyclonic chamber. Preferably, the second collecting region is formed by a collecting cup positioned in the first collecting region.

Typically, a filter assembly is mounted between the working air conduit and the inlet of the suction source. Further, the working air conduit extends through a central portion of the first collecting region of the dirt cup assembly in a preferred embodiment of the invention.

In accordance with yet another embodiment of the invention, at least one of the secondary cyclones has a vortex stabilizer. According to one embodiment, all of the secondary cyclones have a vortex stabilizer. According to another embodiment, the secondary cyclones are frustoconical. Preferably, the vortex stabilizer is located at a bottom portion of the secondary cyclone. Further, the vortex stabilizer can comprise a stabilizer plate. A debris outlet can be formed in the side wall of the secondary cyclone adjacent to the stabilizer plate. Further, the air inlet and air outlet of the secondary cyclone can be located at an upper portion of the secondary cyclone.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a perspective view of an upright vacuum cleaner with a cyclonic dirt separator and dirt cup assembly according to the invention.

FIG. 2 is a sectional view taken along line2-2 ofFIG. 1.

FIG. 3 is an exploded perspective view of a cyclonic separator assembly of the cyclonic dirt separator and dirt cup assembly ofFIG. 1.

FIG. 4 is a sectional view taken along line4-4 ofFIG. 1.

FIG. 5 is a sectional view taken along line5-5 ofFIG. 4.

FIG. 6 is a sectional view taken along line6-6 ofFIG. 3.

FIG. 7 is an exploded perspective view of a dirt cup assembly from the cyclonic dirt separator and dirt cup assembly ofFIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings and toFIG. 1 in particular, anupright vacuum cleaner10 comprises anupright handle housing14 with ahandle grip13 formed at an upper end and pivotally mounted to anozzle base housing16 at a lower end. Thenozzle base housing16 comprises a suction nozzle opening11 on a forward portion thereof. Theupright handle housing14 has anopening15 that receives a cyclonic dirt separator anddirt cup assembly12 comprising acyclone separator assembly18 and adirt cup assembly54. Thedirt cup assembly54 is removably mounted to theupright handle housing14 and includes agrip23 to facilitate insertion and removal of thedirt cup assembly54. Thegrip23 can be separately formed and attached to thedirt cup assembly54 in a commonly known manner, such as with screws. However, thegrip23 can also be integrally formed with thedirt cup assembly54 or can be fastened in other commonly known ways, such as with adhesives or ultrasonic welding.

Referring toFIGS. 2-4, thecyclone separator assembly18 comprises acyclone housing27 having a primary separation region with aprimary cyclone19 and a secondary separation region that receives a plurality ofsecondary cyclones102. The primary separation region is formed by a generally cylindrical primaryseparator side wall17 and has a generally vertical central longitudinal axis A. A primary separatorupper wall35, which is best viewed inFIGS. 2 and 4, extends in a generally horizontal orientation near an upper end of the primaryseparator side wall17. Anannular collar26 is formed centrally in the primary separatorupper wall35 such that theannular collar26 is centered within the primary separation region.

The secondary separation region is separated into two regions, with each of the regions enclosed at its perimeter by a secondaryregion side wall22 radially spaced from the primaryseparator side wall17 and joined to the primaryseparator side wall17 near a lower end by abottom wall25 that extends in a perpendicular manner from an inside surface of the secondaryregion side wall22 to an outside surface of the generally cylindrical primaryseparator side wall17. Together, the secondaryregion side walls22 and exposedportions21 of the generally cylindrical primaryseparator side wall17 between the secondaryregion side walls22, which all terminate in a lower offsetlip24, form an exterior surface of thecyclone housing27. Thus, the exposedportions21 of the primaryseparator side wall17 are exposed to the outside of the cyclonic dirt separator anddirt cup assembly12.

Acyclone cap20 mounted to an upper end of thecyclone housing27 defines a top for thecyclone separator assembly18, and asecondary air manifold29 is supported between thecyclone housing27 and thecyclone cap20. Thesecondary air manifold29 comprises a dependinghollow air duct92 that extends through thecollar26 into the primary cyclone region. As best viewed inFIG. 3, atangential air inlet28 extends through one of the secondaryregion side walls22 and the primaryseparator side wall17 proximate the primary separatorupper wall35 for generating a tangential airflow into the primary separation region.

With continued reference toFIGS. 2 and 3, anexhaust assembly30 is mounted to theannular collar26 in the primary separation region. Theexhaust assembly30 includes a hollowcylindrical cage32 that terminates at a lower end at a radially extendingseparator plate34 having anouter edge52. A plurality ofapertures36 are formed in an axial alignment in thecage32 above theseparator plate34. Thecage32 defines a working air path; air enters the path by flowing radially inward through theapertures36 and then upward through thehollow cage32. Thecage32 and theseparator plate34 are removably mounted to theannular collar26 in the primary cyclone region via a bayonet-type fitting between a projection on theannular collar26 and aslot31 on thecage32 to provide a twist and lock connection. However, it is within the scope of the invention to use other mechanical fastening means to removably mount theexhaust assembly30 to theannular collar26. For example, friction fits, ramped threads, detents, or any other commonly known fastening method can be utilized.

Referring additionally toFIG. 4, a primary cyclonictoroidal chamber48 is defined horizontally between thecage32 and the primaryseparator side wall17 and vertically between the primary separatorupper wall35 and theseparator plate34. In one embodiment, thetangential air inlet28 is vertically aligned between the primary separatorupper wall35 and theseparator plate34 and slightly inclined such that the tangential airflow generated from thetangential air inlet28 is directed in a slightly downward direction tangentially into the primary cyclonictoroidal chamber48.

Referring now toFIG. 4, a working airflow, which is represented by arrows, containing particulate matter, passes through thetangential air inlet28 and into the primary cyclonictoroidal chamber48, where it travels around theexhaust assembly30. As the airflow travels about the primary cyclonictoroidal chamber48, heavier dirt particles P1 are forced toward the primaryseparator side wall17. Due to gravity and axial components of the forces imparted by the working air, the particles P1 fall through agap50 defined between theedge52 of theseparator plate34 and the primaryseparator side wall17. The particles P1 that fall through thegap50 continue to fall into thedirt cup assembly54, where they are collected in a primarydirt collection region56 of thedirt cup assembly54. An upper end of thedirt cup assembly54 is received in a nesting relationship in the lower offsetlip24 of the secondaryregion side wall22 and the exposedportions21 of the primaryseparator side wall17 to seal thecyclone separator assembly18 to thedirt cup assembly54. The primarydirt collecting region56 thereby performs the function of collecting the particles P1 separated from the airflow within theprimary cyclone19.

As the working air traverses through the primary cyclonictoroidal chamber48 and casts the particles P1 toward the primaryseparator side wall17, the working air is drawn inwardly through theapertures36 of theexhaust assembly30. In one embodiment, theapertures36 have an oblong shape, but theapertures36 can have any suitable geometry that prevents the particles P1 from exiting the primary cyclonictoroidal chamber48 through theapertures36. Rather, the particles P1 are urged toward thegap50 by the circulating airflow in the primary cyclonictoroidal chamber48.

Some fine debris can remain in the working air after it passes through the primary cyclonictoroidal chamber48. As shown inFIG. 4, the working air that exits the primary cyclonictoroidal chamber48 through theapertures36 continues through a secondary cyclonetoroidal path90 formed between an inner surface of theexhaust assembly30 and an outer solid surface of theair duct92 depending from thesecondary air manifold29 in a coaxial relationship relative to theexhaust assembly30. The secondary cyclonetoroidal path90 can also be viewed inFIG. 5. As shown inFIG. 4, the secondary cyclonetoroidal path90 directs the working air from theprimary cyclone19 to thesecondary air manifold29, which directs the working air to the plurality ofsecondary cyclones102 located in the secondary cyclone region.

Referring now toFIGS. 2-5 thesecondary cyclones102 are arranged around the primaryseparator side wall17 of theprimary cyclone19 in the two regions of the secondary cyclone region. In particular, thesecondary cyclones102 are arranged in two groups, aright group102A and aleft group102B, with the right and leftgroups102A,102B corresponding to the two regions and positioned on opposite sides of a vertical plane B (FIG. 5) that includes the central longitudinal axis A and extends from back to front to effectively cut thecyclone separator assembly18 in half. Thus, afront gap98 is formed between adjacentsecondary cyclones102 at a front side of thecyclone separator assembly18, and arear gap100 is formed between adjacentsecondary cyclones102 at a rear side of thecyclone separator assembly18. According to the illustrated embodiment, the front andrear gaps98,100 are located diametrically opposite each other. Thetangential air inlet28 is positioned in therear gap100 near theright group102A. The front andrear gaps98,100 are coincident with the exposedportions21 of the primaryseparator side wall17; therefore, none of thesecondary cyclones102 are located in front of the exposedportions21 of the primaryseparator side wall17 to obstruct view of the exposedportions21. The exposedportions21 of the primaryseparator side wall17 can be made of a transparent or translucent material to allow the user to view the primary cyclonictoroidal chamber48 through the front andrear gaps98,100 and through the exposedportions21 of the primaryseparator side wall17. However, only thefront gap98 is viewable when thecyclone separator assembly18 is mounted in theopening15 of theupright handle housing14, as shown inFIG. 1. Additionally, the secondaryregion side wall22 can be made of a transparent or translucent material to allow a user to view thesecondary cyclones102.

As shown inFIGS. 3 and 5, in the illustrated embodiment, theright group102A includes four of thesecondary cyclones102, and theleft group102B includes five of thesecondary cyclones102; however, it is within the scope of the invention for the right and leftgroups102A,102B to comprise any suitable number of thesecondary cyclones102. Further, it is within the scope of the invention to group thesecondary cyclones102 into more than two groups. Alternatively, all of thesecondary cyclones102 can be located on one side of the plane B, wherein the number of thesecondary cyclones102 can range from between one and ten or between three and seven. According to one embodiment, five of thesecondary cyclones102 are located all on one side of the plane B.

Referring again toFIGS. 2-5, thesecondary cyclones102 each comprise a frustoconical housing having aside wall104 that defines a secondarycyclonic chamber101. Eachside wall104 has an upper,larger end106 that defines anaperture118 that functions as both an air inlet and an air outlet for the secondarycyclonic chamber101, as will be described in more detail below, and a lower,smaller end110 forming asecondary debris outlet120 through which particles P2 separated from the working air passes to a secondarydirt collecting region58 of thedirt cup assembly54. Thesecondary cyclones102 in each of thegroups102A,102B are connected to one another at the larger ends106 via ahousing support105 that can either be a separate piece or integrally molded with theside walls104. Each of thesecondary cyclones102 has a central longitudinal axis C (FIG. 2) parallel with the central longitudinal axis A of theprimary cyclone19. According to the illustrated embodiment, the central longitudinal axes A, C of theprimary cyclone19 and thesecondary cyclones102 are generally vertical. Alternatively, one or more of the central longitudinal axes A, C can be inclined relative to the vertical, and thesecondary cyclones102 can be inverted such that thelarger end106 is below thesmaller end110.

The size and shape of thesecondary cyclones102 are important for maximizing separation efficiency. In one embodiment, theaperture118 at thelarger end106 of theside wall104 has a surface area about ten times larger than that of thesecondary debris outlet120 at thesmaller end110. However, acceptable performance is obtained within a ratio of thelarger end106 to thesmaller end110 ranging between about two to one and about twenty to one, preferably between about three and a half to one and about eight and a half to one. The secondaryregion side wall22 is tapered to correspond to the shapes of thesecondary cyclones102 located within the secondaryregion side wall22. The secondaryregion side wall22 tapers from its upper end, where it abuts thecyclone cap20, to its lower end, which is at the offsetlip24.

Other arrangements of thesecondary cyclones102 have been found to perform in an acceptable manner. Configurations of between one and fifteen of thesecondary cyclones102 arranged in split fashion as previously described or completely encircling the primaryseparator side wall17 are contemplated. As can be appreciated, the overall size of the cyclonic dirt separator anddirt cup assembly12 is limited by the size of theopening15 in theupright handle housing14. Therefore, given a fixedmaximum size opening15, as the number of thesecondary cyclones102 increases, the individual size of each of thesecondary cyclones102 must be reduced so that the cyclonic dirt separator anddirt cup assembly12 fits within theopening15. It has been found that in this arrangement with this type of primary cyclone, when thelarger end106 is smaller than one inch in diameter, thesecondary cyclones102 tend to clog with debris. Given this dimensional limitation, groupings of between five and eleven of thesecondary cyclones102 have been deemed acceptable for portableupright vacuum cleaners10 sized similarly to most current commercially available portable upright vacuum cleaners.

As stated above, thesecondary air manifold29 is positioned between thecyclone housing27 and thecyclone cap20. As best viewed inFIG. 3, anair manifold gasket125 is positioned between thesecondary air manifold29 and thecyclone housing27 to form an airtight seal therebetween. A plurality of working air inlet passageways119, which are best viewed inFIG. 6, are formed in thesecondary air manifold29 for dividing the working air that flows from the secondary cyclonetoroidal path90 and directing the divided working air into each of thesecondary cyclones102. The number of the working air inlet passageways119 equals the number of thesecondary cyclones102; each of the workingair inlet passageways119 corresponds to one of thesecondary cyclones102. Referring back toFIGS. 2-4, each of the workingair inlet passageways119 terminates at theaperture118 of the correspondingsecondary cyclone102 to form aninlet121 to thesecondary cyclones102. The working air exits thesecondary cyclones102 through corresponding workingair outlets122 formed in thesecondary air manifold29 and received by the correspondingapertures118. The number of the workingair outlets122 equals the number of thesecondary cyclones102; each of the workingair outlets122 corresponds to one of thesecondary cyclones102. In one embodiment, the surface area of thesmaller end110 of thesecondary cyclones102 is about equal to or greater than the surface area of the workingair outlet122. The workingair outlets122 fluidly communicate with a workingair exhaust chamber123 formed between an upper surface of thesecondary air manifold29 and a lower surface of thecyclone cap20. The workingair exhaust chamber123 is in fluid communication with the hollowair outlet duct92 of thesecondary air manifold29.

Referring nowFIGS. 2,4, and7, thedirt cup assembly54 comprises the primarydirt collecting region56, the secondarydirt collecting region58, a centrally oriented workingair standpipe68, and apost-cyclone filter assembly76. The primarydirt collecting region56 is formed by an upstanding dirtcup side wall64 and an annular dirtcup bottom wall62 having aflat portion61 that surrounds afrustoconical portion63. Thehollow standpipe68 extends upward into the primarydirt collecting region56 from thefrustoconical portion63. According to the illustrated embodiment, thehollow standpipe68 is centered in the primarydirt collecting region56, but it is within the scope of the invention for thehollow standpipe68 to be offset from the center of the primarydirt collecting region56. When thedirt cup assembly54 is mounted below thecyclone separator assembly18, thehollow standpipe68 meets theair outlet duct92 to form a working air conduit that extends through theprimary cyclone19 and thedirt cup assembly54. The mating surfaces between theair outlet duct92 and thehollow standpipe68 are effectively sealed with agasket33 to prevent air leaks therebetween. The dirtcup side wall64 terminates at anupper lip65, and, when thedirt cup assembly54 is mounted below thecyclone separator assembly18, adirt cup gasket83 is positioned between theupper lip65 of thedirt cup assembly54 and the lower offsetlip24 of thecyclone separator assembly18 to prevent air leaks therebetween. The dirtcup side wall64 slightly tapers from theupper lip65 to thebottom wall62. The taper creates an air flow pattern within thedirt cup assembly54 that minimizes debris re-entrainment. Additionally, the taper creates a narrowerdirt cup assembly54 that is sized to facilitate manipulation of thedirt cup assembly54 with only one hand by a user.

To further inhibit re-entrainment of debris, a plurality of upstanding prongs orfingers66 project upwardly from thebottom wall62, particularly from thefrustoconical portion63 of thebottom wall62. Thefingers66 can function in varying arrangements, but in the illustrated embodiment, thefingers66 are arranged generally symmetrically about thehollow standpipe68 centrally located within thedirt cup assembly54. According to one embodiment, thefingers66 are spaced from thestandpipe68. Thedirt cup assembly54 further includes afin70 affixed to or integrally formed with the dirtcup side wall64. Thefin70 is generally rectangular in transverse cross-section and projects radially inwardly from theside wall64 toward thestandpipe68. Optionally, thedirt cup assembly54 can comprise more than one of thefins70 circumferentially spaced around the dirtcup side wall64. Details of acceptable sizing and spacing of thefingers66 and thefin70 are found in U.S. Pat. No. 6,810,557 to Hansen et al., which is incorporated herein by reference in its entirety.

The secondarydirt collecting region58 is formed by a secondarydirt collecting cup75 comprising a pair of collectingunits74 joined by acup support77. Each of theunits74 comprises abottom wall79 and anupstanding side wall81 to form an open top receptacle. The secondarydirt collecting cup75 sits inside the dirtcup side wall64 such that the primarydirt collecting region56 receives the secondarydirt collecting cup75, and thebottom walls79 of the collectingunits74 are spaced from the bottom wall82 of the primarydirt collecting region56. The secondarydirt collecting cup75 is oriented so that the each of the collectingunits74 is positioned directly below one of the right and leftgroups102A,102B of thesecondary cyclones102. In particular, the collectingunits74 are located below thesecondary debris outlets120 of thesecondary cyclones102 to collect the particles P2 that fall therefrom, as illustrated inFIG. 4. In the illustrated embodiment, one of the collectingunits74 is used to collect the particles P2 from more than one of thesecondary cyclones102. However, a series ofindividual collecting units74 can be used to collect debris from each correspondingsecondary cyclone102. The secondarydirt collecting cup75 can be fixedly mounted to thedirt cup assembly54, integrally formed with thedirt cup assembly54, or removably mounted to thedirt cup assembly54.

Thefilter assembly76 comprises afilter cage84 that holds afilter element86. Thefilter assembly76 is located below thestandpipe68 such that working air that flows downward through thestandpipe68 must pass through thefilter assembly76 before reaching an inlet of asuction source87 located downstream from thefilter assembly76. Thefilter cage84 comprises anopen tray85 to removably receive thefilter element86. Preferably, thefilter element86 is an open cell foam filter; however, paper pleated filters and other common filter element types can also be used. Thefilter cage84 is secured to with thebottom wall62 of the primarydirt collection region56 via a quarter-turn bayonet fastener or any other suitable mechanical fastening means, as previously described.

Thedirt cup assembly54 is removably mounted to theupright vacuum cleaner10. Thedirt cup assembly54 is generally vertically adjustable relative to thecyclone separator assembly18, such as by a cam mechanism mounted to theupright handle housing14, so that it can be raised into an engaged and operative position underneath thecyclone separator assembly18. When in this position, theupper lip65 of the dirtcup side wall64 is received within the lower offsetlip24 of thecyclone separator assembly18 and is sealed by thegasket83, which helps prevent thedirt cup assembly54 from being dislodged from thecyclone separator assembly18. To remove thedirt cup assembly54 from thecyclone separator assembly18, such as to discard accumulated dirt, thedirt cup assembly54 is displaced downwardly from thecyclone separator assembly18, such as by the cam mechanism. Once disengaged from the offsetlip24, thedirt cup assembly54 can be slid forward and removed from theseparator18.

Referring toFIG. 4, in operation, thesuction source87, which can be located in either theupright handle housing14 or thenozzle base housing16, generates a working airflow through theupright vacuum cleaner10. Dirty working air enters the cleaner10 at thesuction nozzle opening11 and flows through a suitable conduit (not shown) to thetangential air inlet28 to the cyclonic dirt separator anddirt cup assembly12. The working air traverses around the primary cyclonictoroidal chamber48 and casts dirt particles toward the primaryseparator side wall17, thereby separating the larger particles P1 from the air stream and depositing the larger particles P1, by force of gravity, through thegap50 between theseparator plate edge52 and the primaryseparator side wall17 into the primarydirt collecting region56. The working air exits the primary cyclonictoroidal chamber48 through theapertures36 and flows into the secondary cyclonetoroidal path90 to thesecondary air manifold29. In thesecondary air manifold29, the working air is evenly divided to each of the working air inlet passageways119, which direct the working air to the plurality ofsecondary cyclones102, which are arranged in parallel. After flowing through the working air inlet passageways119, the working air tangentially enters the respectivesecondary cyclones102 at thelarger end106 to create a swirling action within the secondarycyclonic chamber101 defined by therespective side wall104. As the swirling air approaches thesmaller end110 of thesecondary cyclones102, the velocity of the air speeds up and throws the fine secondary particles P2 remaining in the working air toward theside wall104 in a fashion similar to that of theprimary cyclone19. The fine secondary particles P2 exit thesecondary cyclone102 through thesecondary debris outlet120, and the fine secondary particles P2 fall, under force of gravity, into the secondarydirt collecting region58 of thedirt cup assembly54.

The working air in thesecondary cyclones102 is then forced to change direction and exits thesecondary cyclones102 through therespective air outlet122 of thesecondary air manifold29 received by theaperture118. The working air passes through theair outlets122, through the workingair exhaust chamber123, and into theair outlet duct92. The working air then passes downward through theair outlet duct92, through thedirt cup standpipe68, and into thefilter assembly76, where thefilter element86 captures additional particulate material before the working air is drawn into thesuction source87. Optionally, a pre-motor filter (not shown) can be located immediately upstream of thesuction source87 to prevent any remaining debris from entering thesuction source87. Debris that enters thesuction source87 can damage internal components and shorten the useful life of thesuction source87. The working air then passes through an optionalpost-motor filter89, such as a HEPA filter, before exiting theupright vacuum cleaner10.

While the cyclonic dirt separator anddirt cup assembly12 has been described for use with theupright vacuum cleaner10, it is within the scope of the invention to utilize the cyclonic separator anddirt cup assembly12 in other types of vacuum cleaners, including canister vacuum cleaners and robotic vacuum cleaners.

The cyclonic dirt separator anddirt cup assembly12 provides several advantages. For example, thesecondary cyclones102 are arranged around thefirst cyclone19 to reduce the height of the cyclonic dirt separator anddirt cup assembly12. Additionally, because thesecondary cyclones102 form thefront gap100, a user can visually inspect the primary cyclonictoroidal chamber48 through the primaryseparator side wall17 when the exposedportions21 are made of a translucent material. As a result, the user can visually confirm that thecyclonic separator assembly18 is properly functioning and identify the presence of clogs or other potential problems. Furthermore, the working air that exits thesecondary cyclones102 flows downward through the working air conduit formed by theair duct92 and thestandpipe68 directly to thesuction source87. Consequently, the distance that the working air must travel between thesecondary cyclones102 and thesuction source87 is minimized, thereby reducing pressure losses and potential for leaks to develop.

While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible within the forgoing disclosure and drawings without departing from the spirit of the invention, which is defined in the appended claims.

Claims (29)

1. A vacuum cleaner comprising:

a cyclonic separator comprising:

a first cyclone having a side wall defining a first cyclonic chamber for separating contaminants from an air stream as the air stream travels about the first cyclonic chamber from an air inlet to an air outlet; and

a plurality of secondary cyclones downstream from the first cyclone, each of the secondary cyclone having a side wall defining a second cyclonic chamber for further separating contaminants from the air stream as the air stream travels about the second cyclonic chamber from an air inlet to an air outlet, and the secondary cyclones are arranged around the first cyclone side wall and form at least one gap between adjacent secondary cyclones to expose the first cyclone side wall to the outside of the cyclonic separator at the at least one gap;

a nozzle housing including a suction opening coupled with the air inlet of the first cyclonic chamber; and

a suction source coupled to the suction opening and to the first and second cyclonic chambers and adapted to establish and maintain the air stream from the suction opening, through the first cyclonic airflow chamber, and through the second cyclonic airflow chambers.

2. The vacuum cleaner according toclaim 1, wherein the first cyclone side wall is formed of a translucent material at least at the at least one gap to provide an unobstructed view of the first cyclonic airflow chamber through the first cyclone side wall and through the at least one gap in the secondary cyclones.

3. The vacuum cleaner according toclaim 1, wherein the secondary cyclones are arranged in groups.

4. The vacuum cleaner according toclaim 3, wherein one of the groups of secondary cyclones comprises four of the secondary cyclones, and another of the groups comprises five of the secondary cyclones.

5. The vacuum cleaner according toclaim 3, wherein each of the groups of secondary cyclones is enclosed by a side wall spaced from the first cyclone side wall.

6. The vacuum cleaner according toclaim 5, wherein the enclosing side wall of the groups of secondary cyclones is translucent.

7. The vacuum cleaner according toclaim 1 and further comprising an upright housing with an opening that receives the cyclonic separator, and the at least one gap is formed at a front portion of the cyclonic separator for an unobstructed view of the first cyclone side wall when the cyclonic separator is mounted to the upright housing.

8. The vacuum cleaner according toclaim 1 wherein the air inlet to the first cyclone is positioned in the side wall of the first cyclone and distal from the at least one gap.

9. The vacuum cleaner according toclaim 1 wherein the secondary cyclones form two gaps in the array of secondary cyclones, and the air inlet to the first cyclone is positioned in one of the two gaps.

10. The vacuum cleaner according toclaim 9 wherein the two gaps are formed at opposite sides of first cyclone side wall.

11. The vacuum cleaner according toclaim 1 wherein the secondary cyclones are arranged in parallel.

12. The vacuum cleaner according toclaim 11 wherein the secondary cyclones have a generally vertical central longitudinal axis parallel to a central longitudinal axis of the first cyclone.

13. The vacuum cleaner according toclaim 12 wherein the secondary cyclones are frustoconical, and the first cyclone is cylindrical.

14. The vacuum cleaner according toclaim 1 and further comprising a dirt cup assembly mounted below the cyclonic separator.

15. The vacuum cleaner according toclaim 14 wherein the dirt cup assembly comprises a first collecting region for collecting the contaminants separated in the first cyclonic chamber and a second collecting region for collecting the contaminants separated in the second cyclonic chamber.

16. The vacuum cleaner according toclaim 15 wherein the second collecting region is formed by a second collecting cup positioned in the first collecting region.

17. The vacuum cleaner according toclaim 14 and further comprising a hollow standpipe within the dirt cup assembly and that couples the air outlets of the secondary cyclones with an inlet of the suction source through the dirt cup assembly.

18. The vacuum cleaner according toclaim 17 and further comprising a filter assembly mounted between the standpipe and the inlet of the suction source.

19. A vacuum cleaner comprising:

a cyclonic separator comprising:

a first cyclone having a side wall defining a first cyclonic chamber for separating contaminants from an air stream as the air stream travels about the first cyclonic chamber from an air inlet to an air outlet;

a plurality of secondary cyclones downstream from the first cyclone, each of the secondary cyclones having a side wall defining a second cyclonic chamber for further separating contaminants from the air stream as the air stream travels about the second cyclonic chamber from an air inlet to an air outlet;

a dirt cup assembly mounted beneath the cyclonic dirt separator to collect the contaminants separated by the first cyclonic chamber and the second cyclonic chambers;

a nozzle housing including a suction opening coupled with the air inlet of the first cyclonic chamber;

a suction source positioned below the dirt cup assembly and having an inlet fluidly coupled to the suction opening in the nozzle housing through the air inlets and air outlets of the first cyclone and the secondary cyclones, and the suction source is adapted to selectively establish and maintain the air stream from the suction opening, through the first cyclonic airflow chamber, and through the second cyclonic airflow chambers; and

a working air conduit extending through the first cyclone and the dirt cup assembly and fluidly coupling the air outlets of the second cyclonic chambers to the inlet of the suction source.

20. The vacuum cleaner according toclaim 19 wherein the dirt cup assembly comprises a bottom wall and a side wall that form a collecting region to collect the contaminants separated by the cyclonic separator and the working air conduit extends through the bottom wall of the dirt cup assembly.

21. The vacuum cleaner according toclaim 20 and further comprising an air duct fluidly coupling the air outlets of the secondary cyclonic chambers to the working air conduit.

22. The vacuum cleaner according toclaim 21 and further comprising a filter assembly mounted between the working air conduit and the inlet of the suction source.

23. The vacuum cleaner according toclaim 20 wherein the dirt cup assembly comprises further comprises a first collecting region for collecting the contaminants separated in the first cyclonic chamber and a second collecting region for collecting the contaminants separated in the second cyclonic chambers, and the working air conduit extends through the first collecting region.

24. The vacuum cleaner according toclaim 19 wherein the secondary cyclones are arranged in parallel.

25. The vacuum cleaner according toclaim 24 wherein the secondary cyclones have a generally vertical central longitudinal axis parallel to a central longitudinal axis of the first cyclone.

26. The vacuum cleaner according toclaim 25 wherein the secondary cyclones are frustoconical, and the first cyclone is cylindrical.

27. The vacuum cleaner according toclaim 19 wherein the secondary cyclones are arranged around the first cyclone side wall and form at least one gap between adjacent secondary cyclones, and the first cyclone side wall is exposed to the outside of the cyclonic separator at the at least one gap.

28. The vacuum cleaner according toclaim 27 wherein the first cyclone side wall is formed at least in part of a translucent material at the at least one gap to provide an unobstructed view of the first cyclonic airflow chamber through the first cyclone side wall and through the at least one gap in the secondary cyclones.

29. The vacuum cleaner according toclaim 28 wherein the secondary cyclones form two of the gaps that separate two distinct groups of secondary cyclones, and the air inlet to the primary cyclone is positioned in one of the two gaps of secondary cyclones.

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